Google Inc. finally sealed the deal with the Motorola Mobility on Tuesday.

The Internet giant closed the $12.5 billion deal nine months after it announced to broaden its horizon by foraying into the cellphone business. Now with this most expensive and riskiest acquisition in its 14-year history, Google will be in charge of a major smartphone, tablet and set-top box maker and will own a portfolio of useful patents.

Google, however, already entered the software arena four years ago with its Android software.

Dennis Woodside, was named as Motorola's CEO. He replaces Sanjay Jha, 49, who has been an exceptional CEO for the company.